The ice went out on Christmas Lake last week, and soon a new gate will go up at its only public boat ramp, signaling the start of what may be the most contentious boating season yet in Minnesota's two-decade fight over zebra mussels and other invasive species.

The gate, installed in November, is more than a method to keep invasive species out of one of the most pristine and exclusive lakes in the metro area. Some see it as a challenge to individual privacy and a virtual Minnesota birthright -- unfettered access to any lake or river in the state.

Those two imperatives -- protecting the lakes and keeping them open to all -- are at the heart of a lawsuit filed last week by three west-metro lake associations against the Minnesota Department of Natural Resources (DNR). The associations claim the state has failed to devise a comprehensive plan against invasive species and has thwarted their efforts to protect the lakes they treasure.

"It's not clear to the general public that the battleground for zebra mussels in 2012 is Minnesota," said Joe Shneider, president of the Christmas Lake Homeowners Association, one of litigants. "Every state east of us has lost the war," he said.

But some say the lawsuit and the gates will only inflame the debate, not solve the problem.

"Those aren't their lakes," said Vern Wagner, executive director of Anglers for Habitat. "Those lakes belong to the citizens of Minnesota.''

, Associated Press - Ap

Zebra mussels have been confirmed in nine Minnesota rivers and 29 lakes – so far.

DNR officials say they are doing more than ever to fight such invasive species as zebra mussels and milfoil. The Legislature has increased funding from $3.8 million in 2010 to an expected $8.6 million this year. And now the DNR is asking for laws that would require boat owner education, give the agency authority to conduct mandatory boat inspections, and allow it to delegate that same authority to counties and cities.

When critics complain about the lack of a statewide plan, what they really mean is that they want the state to inspect every boat before launch in any of the state's 13,000 lakes, said Luke Skinner, supervisor of the state's invasive species program.

Not only would that be breathtakingly expensive, officials said, but it raises profound questions about the reach of government into the privacy of the state's 800,000 boats.

"These are big issues that the DNR can't be the sole arbiter on," said Steve Hirsch, director of the DNR's division of water and ecological resources. "It gets into what level of government intrusion is appropriate."

'Incompatible'

There is no question that invasive species are a growing threat. Many lakes are choked with milfoil, and zebra mussels have been confirmed in nine rivers and 29 lakes, and might be in 30 more that are connected to them. The striped mollusks consume so much plankton that they can devastate entire food systems. However, despite their spread westward from the Great Lakes since the late 1980s, so far only Lake Erie has had been severely affected, say biologists.

Even more terrifying species could be on the way. The zebra's uglier cousin, the quagga mussel, has infested parts of the Great Lakes. Hydrilla, another milfoil-like plant, and Asian carp, which have crashed ecosystems in rivers in the South, are marching northward. And consider the snakehead carp, found in some lakes and rivers in the East -- a voracious carnivore that can live out of water for three days and wriggle across dry land.

The best protection against all of them are boats that are clean, drained and dry so they do not carry vegetation on their trailers or contaminated water in their bilges and wells.

Still, all it takes is one careless boat owner, and a Pandora's box is opened into Minnesota's greatest pride and joy.

"Aquatic invasive species in the land of 10,000 lakes are incompatible with our way of life," said Jeff Forester, executive director of the Minnesota Seasonal and Recreational Property Owners Association. "We have to do what we have to to stop them."

Zebra mussels were found two years ago in Lake Minnetonka, the most heavily used lake in the Twin Cities, and they have now spread into most of its bays. Last year, frustrations ramped up in Douglas and Otter Tail counties when two residents brought zebra mussels into uninfested lakes by moving boat lifts from infested lakes.

Then, last year, the Lake Minnewashta Preservation Association in Carver County persuaded the county board and the Minnehaha Creek Watershed District to jointly fund a $31,000 boat inspection program at Lake Minnewashta Regional Park. Three other lake associations -- Christmas, Lotus and Bavaria -- pushed for mandatory inspections at the Minnewashta site for boats entering all four lakes, and wanted to install gates to enforce it.

The DNR balked.

Backlash?

Gates "are inherently controversial," DNR officials said in a February letter to the watershed district. Combined with mandatory inspections, they would likely create a backlash against efforts to control invasive species. Most importantly, they argued, the DNR does not have the legal authority to require inspections, and neither do local governments.

The lawsuit filed last week argues that the DNR does have the authority. And, Shneider said, gates and restricted access are common at state, federal and county parks.

Mandatory boat inspections are feasible, he argues. Oregon, for instance, requires inspections of all boats that enter the state. And Lake Tahoe has a highly effective, sophisticated boat inspection and decontamination program with guards at every entry point, which Minnesota could emulate, he said. "The model is scalable," he said.

The price?

About $22 million to $28 million annually for boat inspection stations around the state -- about 10 times more than the state is spending now, according to a report the DNR commissioned earlier this year. If paid for by surcharges on boat licenses, the cost of a three-year license could jump by $35 or more.

Wagner, of Anglers for Habitat, said it's ironic that the lawsuit was filed now, when the Legislature is addressing the issue with new funding and laws that give the DNR more authority. He said he fears that it may spark many more suits. If they prevail in court, Minnesota's outdoor culture will never be the same, he said.

"Let's shut these lakes down," he said. "If you want to go fishing, you fish between 8 a.m. and 7 p.m. and you do it after you've been through a checkpoint Charlie."